Boat anchors of various types have been known since antiquity and man has constantly sought to improve the efficiency of anchors and to make them more practical. A major advance in the art took place when the Danforth anchor came into being. The Danforth anchor has the flukes pivoted in relation to the shank and may also include crown elements or plates positioned rigidly on the fluke structure. The Danforth anchor, as well as others of the same general type, can be made much lighter than traditional types while still maintaining deep penetrating ability due to the construction and geometry of the anchor. Anchors of the Danforth type have found great utility in connection with smaller boats used for fishing and/or recreation.
A recognized attribute of all pivoted fluke anchors and particularly those possessing crown elements is that the anchors are non-fouling in comparison to rigid traditional types and much more easily retrievable when fouled on the bottom. The development of loop or pocket shanks has increased the retrivability of pivoted fluke anchors still further in the recent prior art.
Prior U.S. patents of interest include the following:
U.S. Pat. No. 2,651,277 (1953) Jenshak PA0 U.S. Pat. No. 2,722,191 (1955) Johnson PA0 U.S. Pat. No. 3,263,642 (1966) Wilson PA0 U.S. Pat. No. 4,210,092 (1980) Battersby
An object and feature of the present invention is the provision of a sliding shackle anchor which will respond to the pull on an anchor line in a manner to free the anchor blade from overlying obstructions in a quick response. When a power winch is utilized for an anchor, it is extremely important that the anchor release quickly. Otherwise, the power winch can act to pull the boat down into the water and possibly capsize the craft. When utilizing a power winch or hand crank to reel in the anchor cable, a tension develops which tends to pull the boat down, especially when the anchor is fouled on the bottom by a rock or a root or other obstruction. Under these conditions, the boat is generally downwind from the anchor and a wave hitting the prow of the boat will put a sharp and sudden load on the cable and the anchor. This very often will snap the cable or break the anchor itself or the fastening links.
Thus, it is an object and feature of the invention that, as the anchor cable is reeled in, the cable connection to the anchor will move into a self-releasing position before the boat gets directly above or crosses over the anchor. The anchor is lightweight but designed to grab into the bottom of the body of water.
It is, therefore, an object of the invention to provide an anchor construction which is sturdy and disposed to grab the lake bottom readily but also to function for quick release.
Other objects and features of the invention will be apparent in the following description and claims in which the invention is described together with details to enable persons skilled in the art to practice the invention, all in connection with the best mode presently contemplated for the invention.